Top-load zip line trolleys with variable speed control

ABSTRACT

A top-load trolley with speed control system is disclosed. The trolley has a housing of metal plates with a series of fixed and movable parts mounted between. A number of rollers are moveably mounted in-line within the housing such that they may ride atop of a zip line and support the weight of the trolley and a passenger. An additional roller is placed in opposition to the load-bearing rollers, arranged to contact the zip line along its underside. Thus, at least three rollers may be configured to produce an adjustable amount of friction on the zip line, thereby providing a more controlled speed down a zip line course. Additionally, an emergency brake mechanism that may be used in conjunction with the top-load trolley with speed control system is disclosed.

The present application claims the benefit of U.S. Provisional Application No. 62/451,699, filed Jan. 28, 2017, and of U.S. Provisional Application No. 62/453,914, filed Feb. 2, 2017, the contents of each of which are incorporated by reference in their entirety as if fully set forth herein.

BACKGROUND OF THE INVENTION 1. Field of the Invention

The invention relates generally to slowing and stopping passengers on a zip line, and more particularly, to zip line trolleys with variable speed control mechanisms.

2. Description of Related Art

A zip line is a tensioned cable, typically made of aluminum or steel wire rope, that is strung between two objects, usually at least several meters above ground level. Zip lines are usually used for amusement and sight-seeing: a harness-wearing rider is suspended from the zip line by a trolley that rides on the zip line, and the trolley carries the rider across the zip line. Zip line heights of up to 100 meters have been used. Thus, while a zip line ride may be thrilling for the rider, that thrill can come with potentially significant dangers, mostly resulting from height and speed.

The speed of a rider along a zip line depends on several factors, including the incline of the zip line, the weight of the rider, friction between the trolley and the line, and wind speed and direction. In order to reach the other end of the line, a rider must accumulate enough speed and momentum to reach the other side. If the trolley is too slow (e.g., because the zip line is not inclined steeply enough) friction and other factors may cause the trolley to stop moving in the middle of the line, leaving the rider stranded and requiring course personnel to go out onto the line and haul the trolley in, a difficult process made more difficult and dangerous by the height.

While lack of sufficient speed is a problem, too much speed is also a problem. Simply put, zip line riders need some mechanism to stop. In some cases, zip liners are simply issued thick leather gloves, and are expected to slow down by grabbing or brushing against the zip line above them. Dislocated shoulders can result from this maneuver.

In recent years, there have been some attempts to provide mechanical braking systems for zip line trolleys. One general type of system, exemplified by U.S. Patent Application Publication No. 2011/0162917 to Steele et al., requires extensive modifications to the typical course and equipment, and has not been widely used. Another more recent patent, U.S. Pat. No. 9,004,235 to Randy Headings, substitutes a mechanical brake for a gloved hand. More specifically, in this patent, a housing is connected to the trolley. The housing has a downwardly-facing brake pad faces the zip line. When a rider taps or holds the exterior of the housing, the brake pad rubs against the zip line and slows the trolley. This solution may be safer than the gloved-hand approach, but it is no more efficient and risks slowing the rider too much.

U.S. Pat. No. 9,021,962, the work of the present inventor that is incorporated by reference in its entirety, discloses an external brake that can be set near the end of a zip line. When a trolley contacts the brake, sets of wheels guided by angled guide slots within the brake apply gradually increasing, rolling pressure to the zip line to slow and arrest the trolley. In some embodiments, the brake may also physically capture the trolley so that it can be hauled in if necessary. Devices in accordance with this patent have found commercial success on zip line courses around the world, but this device is designed only to brake and capture a trolley near the end of a course; it is not designed to regulate the speed of a trolley over the entire zip line. Speed regulation can be important to the operation of a zip line course. In addition to basic rider safety considerations, if a line must be closed temporarily, for example, due to high winds causing excessive speed, the loss of revenue can amount to thousands of dollars.

There have been some attempts to integrate speed control systems into trolleys. For example, U.S. Pat. No. 8,234,980 to Boren et al. has a trolley with a wheel that is mounted on a pivot. A spring-driven mechanism can be used to vary the position of the pivotable wheel slightly, so as to exert more pressure downwardly on the zip line. However, the pivotable wheel is not in a position of particular mechanical advantage relative to the zip line, and must work in conjunction with other elements to slow the trolley—for that purpose, this patent also discloses a frictional brake shoe in contact with the zip line.

SUMMARY OF THE INVENTION

One aspect of the invention relates to a trolley for zip lining that has one or both of two features: a top-loading feature that allows the trolley to be set on a zip line while a passenger is connected to it, and prevents the trolley from detaching from the zip line once it is set; and a variable speed control system. In the variable speed control system, two main rollers rest on the zip line and carry the load of trolley and passenger in operation. A third roller, placed in opposition to the first two, increases friction on the zip line, and may cause a localized bending deformation in the zip line, in order to slow it. The position of the third roller is selectable, and allows the degree of speed control to be varied.

Another aspect of the invention relates to trolleys for zip lining that have a top-loading feature, allowing the trolley to be seated on the zip line through a channel that is formed or formable along a top edge of the trolley.

Other aspects, features, and advantages of the invention will be set forth in the description that follows.

It is understood that both the foregoing general description and the following detailed description are exemplary and exemplary only, and are not restrictive of the invention as claimed.

BRIEF DESCRIPTION OF THE DRAWING FIGURES

The invention will be described with respect to the following drawing figures, in which like numerals represent like elements throughout the figures, and in which:

FIG. 1 is a perspective view of one end of a typical zip line course set-up;

FIG. 2 is a perspective view of a zip line trolley with a speed control system in isolation, according to one embodiment of the invention;

FIG. 3 is a side elevational view of the zip line trolley in isolation with the speed control system in phantom lines, with the trolley set to the maximum speed setting;

FIG. 4 is a front elevational view of the zip line trolley with speed control system, in isolation;

FIG. 5 is a partial schematic view of the zip line trolley with the speed control system in isolation, with the trolley set to the maximum speed setting;

FIG. 6 is a partial schematic view of the zip line trolley with the speed control system in isolation, with the trolley set to the medium speed setting;

FIG. 7 is a partial schematic view of the zip line trolley with the speed control system in isolation, with the trolley set to the minimum speed setting;

FIG. 8 is a perspective view of an additional embodiment of the zip line trolley with speed control system in isolation, with the trolley set to a minimum speed setting;

FIG. 9 is a set of successive side elevational views of the zip line trolley with the speed control system, illustrating the process of engaging the trolley to a zip line, with the trolley set to the minimum speed setting;

FIG. 10 is a side elevational view of the zip line trolley with speed control system in isolation, with the trolley set to a maximum speed setting;

FIG. 11 is a partial schematic view of the zip line trolley with the speed control system in isolation, with the trolley set to the maximum speed setting;

FIG. 12 is a partial schematic view of the zip line trolley with the speed control system in isolation, with the trolley set to the second highest speed setting;

FIG. 13 is a partial schematic view of the zip line trolley with the speed control system in isolation, with the trolley set to the medium speed setting;

FIG. 14 is a partial schematic view of the zip line trolley with the speed control system in isolation, with the trolley set to the second lowest speed setting; and

FIG. 15 is a partial schematic view of the zip line trolley with the speed control system in isolation, with the trolley set to the minimum speed setting;

FIG. 16 is a perspective view of the zip line trolley with the speed control system in isolation, with the trolley set to a minimum speed setting, illustrating an optional handle attachment;

FIG. 17 is a rear elevational view of the optional handle attachment, in isolation;

FIG. 18 is a front elevational view of the optional handle attachment, in isolation;

FIG. 19 is a rear elevational view of the optional handle attachment, in isolation;

FIG. 20 is a perspective view of a secondary brake, installed on a zip line;

FIG. 21 is an exploded view of the secondary brake, in isolation.

FIG. 22 is a side elevational view of the secondary brake installed on a zip line, disengaged; and

FIG. 23 is a side elevational view of the secondary brake installed on a zip line, engaged.

DETAILED DESCRIPTION

Reference will now be made in detail to exemplary embodiments of the invention, some aspects of which are illustrated in the accompanying drawings.

FIG. 1 is a perspective view of a zip line course in use, generally indicated at 10. In the course 10, a zip line 12 is suspended between two supports 14, only one of which is shown in the view of FIG. 1. A trolley 16 is mounted on the zip line 12, and carries a passenger P, who wears a harness 18 that is connected to the trolley 16 by a tether 20. Standard carabiners and other such hardware and equipment may be used to make that connection. Ahead of the trolley 16, and close to the support 14, primary and secondary brakes 22, 24 stand ready to slow and stop the trolley 16 as it nears the support 14. In addition to those safety mechanisms, as will be explained below in more detail, the trolley 16 includes its own speed control mechanism.

As shown in FIG. 1, the primary and secondary brakes 22, 24 are installed directly onto the zip line 12 and are each connected by a separate rope or line 26, 28 to the zip line 12, although in other embodiments, they may instead be connected directly to the support 14. In some embodiments, in order to prevent the lines 26, 28 from swinging in the wind, they may be provided with a magnet or a series of magnets that are ferromagnetically attracted to the zip line 12.

The primary brake 22 may be assumed to be that described in U.S. Pat. 9,021,962, the contents of which are incorporated by reference in their entirety, and is typically thrown or slid along the zip line 12 some distance away from the support 14, so that the trolley 16 will contact the primary brake 18 some distance before the support 14, giving the brake 22 sufficient space to gradually stop the trolley 16 and the passenger P. As will be described in more detail below, the primary brake 22 is specially adapted to receive and capture the trolley 16. This feature may be advantageous if, for example, a passenger P has insufficient speed to reach the end of the zip line course 10, a course operator may retrieve the passenger P by pulling the primary brake line 26 once the primary brake 22 is attached to the trolley 14.

By contrast, the secondary brake 24 is arranged at an appropriate point on the zip line 12 between the primary brake 18 and the support 14, generally at a short distance from the support 14. It ensures that the trolley 16 and passenger P are stopped before impacting the support 14. Typically, that distance between the secondary brake 24 and the support 14 might be on the order of 10-15 feet (3-5 meters), although greater or lesser distances may be used so long as the passenger P arrives at the end of the zip line course 10 and lands safely.

It should be understood that although FIG. 1 illustrates both primary and secondary brakes 22, 24, some courses may not require such brakes, and some course operators may choose not to use them. Thus, although the trolley 16 with its speed control mechanism is advantageously used along with brakes 22, 24, it need not be.

Top-Mount Zip Line Engagement

A traditional trolley, illustrated, for example, in FIG. 7 of U.S. Pat. 9,021,962, is mounted on the zip line by resting its rollers on the zip line. A pair of flanges with aligned openings extends below the zip line when the trolley is mounted, and a carabiner, or another similar piece of external hardware, is inserted through the slots to secure the trolley to the zip line. By contrast, the trolley 16 has an entirely different mounting mechanism: it mounts the zip line 12 from its top.

The trolley 16 has a housing, which is comprised of sets of side plates. More specifically, on each side of the trolley 16, there is a larger, generally L-shaped housing plate 32 and a relatively smaller, generally trapezoidal housing plate 34. They are spaced to define an L-shaped channel 36 between them. The channel 36 begins along the center of the top edge of the trolley 16. The two sides of the trolley 16 are roughly mirror images of one another—the L-shaped channel extends forwardly on one side of the trolley 16 and rearwardly on the other side of the trolley 16. The housing plates 32, 34 on one side of the trolley 16 need not precisely match their counterparts on the opposite side, as long as they provide the same overall shape, the L-shaped channels 36 are in the correct orientations, and components can be secured between sets of housing plates 32, 34, as will be described below in more detail.

The sets of housing plates 32, 34 have a number of components mounted between them, some movable and some fixed. A gate mechanism, in the illustrated embodiment comprised of upper and lower pivoting gates 38, 40, blocks the channel 36, acting much like an independent set of carabiner gates. FIG. 3, a side elevational view, shows both gates 38, 40, the opening for and extent of the channel 36, and the mirror-image nature of the housing plates 32, 34.

To place the trolley 16 on the zip line 12, one orients the trolley 16 such that the zip line 12 extends orthogonal to the channel 36 (and orthogonal to the plane of FIG. 3). One then pushes the trolley 16 up, in the process pivoting and dislodging the gates 38, 40, until the zip line 12 is within the channel 36, inside the gates 38, 40. As will be described below in more detail, it may be necessary to set components of the trolley 16 to certain positions in order to permit the zip line 12 to be inserted fully. One can then swivel the trolley 16 so that the zip line 12 extends forwardly-rearwardly, in the plane of FIG. 3.

The gates 38, 40 are biased toward the closed position illustrated in FIGS. 2 and 3. Once the zip line 12 is past the gates 38, 40, it can only exert upward force on the gates 38, 40, and a pin 42 on the upper gate 38 prevents that gate 38 from rotating counterclockwise enough to allow the gates 38, 40 to open upward. Thus, once the zip line 12 is within the gates 38, 40, it stays in the channel 36 until the gates 38, 40 are manually opened and the trolley 16 is removed from the zip line 12.

The gates 38, 40 may be biased toward the closed position of FIGS. 2 and 3 by any conventional means, including springs, such as torsional springs. However, in the illustrated embodiment, magnets 44 on the gates and mounted within the housing plates 32, 34 exert a spring-like force on the gates 38, 40, biasing them toward the closed position. As those of skill in the art will appreciate, the poles of the magnets 44 are arranged such that the position illustrated in FIGS. 2 and 3 align opposite poles of adjacent magnets 44, creating an attractive force, while moving the gates 38, 40 toward the open position brings the same poles of adjacent magnets 44 closer together, creating a repelling magnetic force.

As those of skill in the art will appreciate, when the trolley 16 is in the position of FIG. 3, the zip line 12 cannot pass into the body of the trolley 16 much beyond the gates 38, 40, as the interior space is obstructed by the lower rollers 50, 52, and the pivoting plate 60 and bracket 58 to which they are connected. Therefore, these components 50, 52, 58, 60 are adapted to be pivoted out of the way when one is placing the trolley 16 on the zip line 12. This is achieved by first pivoting the bracket 58 of roller 50 clockwise around its axle 70, until an upper tip 59 of the bracket 58 is underneath the head or tip 61 of the pivoting plate 60 of roller 52. Then, the plate 60 can be rotated counter-clockwise, thus pushing and further rotating the bracket 58 downward until both rollers 50, 52, plate 60, and bracket tip 59 are flush, or nearly flush, with a lower edge of the channel 36. When the rollers 50, 52, pivoting brackets 58, 59 and the pivoting plates 60, 61 are disposed in this lower position, the channel 36 is unobstructed and ready to receive the zip line 12.

FIG. 3 also illustrates an optional capture barb 72 that allows the trolley 16 to positively engage and be captured by a zip line brake 22 or another device. The capture barb 72 is pivotably mounted to the housing plates 32, 34 of the front end of the trolley 16 at an axle 74. The barb 72 is biased toward the upward position illustrated in FIG. 3 and functions like a typical unidirectional barb: when an object, such as a primary brake 22, contacts it, the force of the contact rotates the barb 72 clockwise, toward a position flush with the housing 32, 34. The front surface of the barb 72 may act as a cam surface, directing the contacting object over and past the barb 72. Once that object passes, the barb 72 pops back up again, engaged with, for example, a primary brake 22. A pin 73 connected to the barb 72 rides in an arcuate slot 75 in the housing plate 34 and thus constrains the motion of the barb 72.

Typically, the barb 72 would lock into a cavity provided in the brake 22. When engaged with the primary brake 22, an operator may pull the brake 22, and the securely engaged trolley 16, with a primary brake line 26—thus, the capture barb 72 acts as a safety device, potentially preventing a passenger from being stranded on the zip line 12. Like the gates 36, 38, the capture barb 72 is resiliently biased toward the position of FIG. 3 by magnets 44.

Speed Control Mechanism

As can be appreciated from FIGS. 2-3, the trolley 16 carries four rollers 46, 48, 50, 52. The upper two rollers 46, 48 are mounted on fixed axles 54, 56 between the housing plates 32, 34. These two rollers 46, 48 are constructed and arranged to rest on the zip line 12 and to carry the load of the trolley 16, including the passenger P.

The other two rollers 50, 52 are pivotably mounted within the trolley 16 and are aligned relative to the upper two rollers 46, 48 such that they engage the bottom side of the zip line 12. The third roller 50, located toward the front of the trolley 16, is carried by the rotating bracket 58, described above, and contains a clutch bearing that prevents it from rolling backwards. Thus, when the third roller 50 is pivoted into the upward position illustrated in FIG. 3, it engages the zip line 12 and prevents the trolley 16 from rolling backwards. Magnets, not shown in FIG. 3, bias the bracket 58 toward the upward position illustrated in FIG. 3. The third roller 50 is optional, and may be placed above or below the zip line 12.

The fourth roller 52 is carried by a pivoting plate 60, the shape of which resembles the silhouette of a bird, and rotates on an axle 62 connected to the plate 60. The pivoting plate 60 was described, in part, above. The plate 60 itself rotates about a pivot or axle 64 spaced from the axle 62 about which the fourth roller 52 rotates. The far end or tail of the plate 60 is connected to a linkage, generally indicated at 66, by means of a pin 68. The fourth roller 52 is positioned and adapted to create a rolling three-point bending deflection in the zip line 12, thereby slowing the trolley 16 as it moves across the zip line 12. The extent of that deflection, and thus, the extent of the slowing or braking effect that it provides, depends on the position of the fourth roller 52. The position of the roller 52 is controlled by the linkage 66.

FIG. 4 is a front elevational view of the trolley 16, illustrating the path of the zip line 12 through the body of the trolley 16. As can be appreciated in FIG. 4, and as was described above, the upper rollers 46, 48 are fixedly mounted to the housing 32, 34. All four rollers 46, 48, 50, 52 are aligned to engage the zip line 12.

FIGS. 5-7 are simplified partial schematic views of the trolley 16, illustrating essentially only the first roller 46, the second roller 48, and the fourth roller 52, with its mounting plate 60 and associated linkage 66. The zip line 12 is shown in phantom, as it would be positioned while the trolley 16 is in position on the zip line 12. These figures illustrate the manner in which the speed control mechanism of the trolley functions. In short, movement of the linkage 66 moves the fourth roller 52 either closer to or farther away from the zip line 12, causing more or less slowing and braking as the trolley 16 moves. As was described briefly above, this may cause increased friction between the fourth roller 52 and the zip line 12, localized deflection of the zip line 12 by rolling three-point bending, or a combination of both. It should be understood that while this description uses certain mechanical terms—including “three-point bending” and “friction”—for the likely effects of the slowing mechanism on the zip line 12, the exact means by which the slowing effect is produced are immaterial as long as the slowing mechanism actually slows the trolley 16 when it is used.

FIG. 5 illustrates the trolley 16 set to the maximum speed setting (which is also the setting that provides the least braking). The adjustable linkage 66 is primarily responsible for any adjustment of vertical or horizontal spacing to the lower roller 52, relative to the two upper rollers 46, 48.

Within the linkage 66, a pin 68 makes a pivoting connection between the plate 60 that carries the fourth roller 52 and a gear selector arm 76. The linkage 66 also comprises a constrained arm 80 that terminates in an opening or loop 86. The constrained arm 80 is constrained because it is sandwiched between two adjacent lower tongues 81 of the body of the trolley 16. Each tongue 81 has a long slot 83 formed in it, and a carabiner 85 goes through the slots 83 and the opening or loop 86 at the end of the constrained arm 80, fixing the position of the constrained arm 80 while the carabiner 85 is attached. Typically, that carabiner 85 would be a locking carabiner, although any sort of hardware may be used.

An upper end 87 of the constrained arm 80 comprises a smooth, curved surface, broken by a number of slots 82. In essence, the upper end 87 resembles, and somewhat behaves as, a partially-toothed gear. The gear selector arm 76 abuts the upper end 87 of the constrained arm 80 and has an upper portion that includes a pawl or catch 84. The arrangement of the elements 84, 87 is such that the catch 84 may slide freely along the curved surface of the upper end 87 of the constrained arm 80 until it drops into one of the slots 82. When the catch 84 is engaged with a slot 82, the gear selector arm 76 is secured in position, the fourth roller 52 is locked in a corresponding position, and the trolley 16 is ready for use. The catch 84 is resiliently biased, again by magnets 44, toward engagement with the slots 82 and moves within the gear selector arm 76. The locations of the slots 82 along the upper end 87 of the constrained arm 80 are chosen to correspond with desired positions of the fourth roller 52 and may vary depending on the speed control requirements of a particular zip line course 10, or the preferences of rider P.

As was noted above, in FIG. 5, the adjustable linkage 66 of trolley 16 is set to the maximum speed setting. At the maximum speed setting, a generally acute angle is formed between the gear selector arm 76 and the constrained arm 80. In this position, fourth roller 52 is in is lowest allowed position and has minimal contact, if any, with the zip line 12. As can be seen in FIG. 5, there is no or essentially no deflection of the zip line in this position.

FIG. 6 is a partial schematic view of the zip line trolley 16 similar to the view of FIG. 5, with the trolley 16 set to a medium speed setting (alternatively, a “moderate” braking/slowing setting). At the medium speed setting, the gear selector arm 76 is raised and forms a generally orthogonal angle between the gear selector arm 76 and the constrained arm 80. This rotates the pin 68, and thus, the connecting plate 60, clockwise, raising the roller 52 slightly, relative to the maximum speed setting, and bringing it into contact with the zip line 12. The resulting position of the roller 52 may force at least some rolling deflection in the zip line 12 between the upper rollers 46, 48 and lower roller 52, and it may increase the normal force at the interface, and thus, the amount of friction between the fourth roller 52 and the zip line 12.

In FIG. 7, by contrast, the speed control mechanism is set to a minimum speed setting, in which the gear selector arm 76 is raised to its highest position, generally forming an obtuse angle between the gear selector arm 76 and the constrained arm 80. This drops the pin 68 to its lowermost allowed position, located to the left and slightly below the gear selector axle 78. This, in turn, pivots the plate 60 slightly further in a clock-wise direction around its axle 64, which also brings the fourth roller 52 higher, where it may make contact with the bottom of zip line 12 and exert significant force, producing a greater slowing effect than in the position of FIG. 6.

While FIGS. 5-7 illustrate some of the possible positions of the gear selector arm 76 relative to the constrained arm 80 (e.g., acute, orthogonal, obtuse), these positions may change depending the spacing of the slots 82, operator preferences, or the diameter of the zip line 12. Additionally, the sense of movement of the gear selector arm 76 may, for example, be inverted (e.g., when the gear selector arm 76 forms an acute angle with respect to the constrained arm 80, the lower roller 52, may be disposed in an upper most position, thus applying a maximum amount of deflection—being the lowest speed control setting). While FIGS. 5-7 illustrate three possible speed control 30 settings, any number of settings may be provided, according to operator or rider P preference.

Ultimately, the speed should be chosen such that, given particular zip line course conditions (wind, inclination, passenger weight, and zip line length, to name a few), the passenger P will have sufficient energy to reach the end of the zip line 12 without having so much energy that he or she comes in at an uncontrollable speed. (Although the primary and secondary brakes 22, 24, if present, can dissipate some excess energy near the end of the zip line 12.)

FIG. 8 is a perspective view of another embodiment of a zip line trolley, generally indicated at 120. The trolley 120 has both a top-loading feature and a speed control mechanism, but both are implemented differently than in the trolley 16 described above.

As can be appreciated from FIG. 8, the trolley 120 has a housing, which is comprised of paired sets of side plates 122, 124. More specifically, on each side of the trolley 120, there is a larger, generally Y-shaped housing plate 122 and a relatively smaller housing plate 124. Along a lower portion of the larger plate 122, a straight slot 126 extends diagonally, forming a generally acute angle relative to a vertical line. The two sides of the trolley 120 are generally mirror images of one another—the slot 126 extends forwardly on one side of the trolley 120 and rearwardly on the other side of the trolley 120.

The sets of housing plates 122, 124 have a number of components mounted between them, some movable and some fixed. As can be seen in FIG. 8, upper rollers 128, 130 are rotatably mounted on axles 148, 150 between the housing plates 122, 124, and are constructed and arranged to ride on top of the zip line 12 (not shown in this view) and to carry the weight of the passenger P. A lower roller 132 is rotatably mounted to the larger housing plates 124, and is expected to ride below the zip line 12. Whereas in the previous embodiment of the trolley 16, the lower roller 52 pivots in a generally upward and downward direction, the lower roller 132 of trolley 120 acts as an axle 134 around which upper rollers 128, 130 pivot, as will be described in more detail below.

A bracket 154 is suspended within the housing 122 on a load-bearing bar 158 which is mounted within the slots 126 and is adapted to move along the slots 126. The bracket 154 has a recess 156 (i.e., a curved depression) that has essentially the same curvature as a circumference of the lower roller 132. As will be described below in more detail, the bar 158 also passes through a plate 160 with a long slot.

An additional, optional upper roller 136 is rotatably mounted such that the roller 136 rides above the zip line 12 during operation. The roller 136 is attached to a pair of corresponding links 138. The opposing sides of the links 138 are moveably mounted to the housing 122, 124 at the rear end of the trolley 120. The links 138 and roller 136 are expected to pivot around a link axle 140. This optional upper roller 136 contains a clutch bearing that allows the trolley 120 to roll forward (i.e., down slope on the zip line 12), while preventing the trolley 120 from rolling backwards on the zip line 12, as was described above. While the roller 136 of the illustrated embodiment is adapted to ride along an upper surface of the zip line 12, the roller 136 may also be configured to ride along a lower surface of the zip line 12 in other embodiments.

Like the trolley 16, the trolley 120 also includes an optional capture barb 142 that would allow the trolley 16 to positively engage and be captured by a zip line brake 22 or another device. The capture barb 142 operates in much the same way as the capture barb 72 described above, and is biased toward the position illustrated in FIG. 8 by magnets.

Top-Mount Zip Line Engagement

The trolley 120 also has a top mounting mechanism, and is constructed and arranged such that the zip line 12 cannot be inserted into the trolley 120 or removed from it unless the trolley 120 is moved into very specific positions. Thus, the trolley 120 itself acts as a safety mechanism to prevent accidental detachment from the zip line 12.

FIG. 9 is a set of successive side elevational views of the trolley 120, illustrating the process by which the trolley 120 is mounted on the zip line 12. To place the trolley 120 on the zip line 12, one orients the trolley 120 such that the zip line 12 extends orthogonal to the top center edge of the trolley 120.

As can be appreciated from FIG. 9, the upper edge of each side of the housing 122 traverses down and across in an L-shape, and as with the trolley 16, the housing plates 122 are mirror images of one another, meaning that the L extends forward on one side and reverse on the other. The rollers 128, 130 are pushed together and the housing 122, 124 rotates, relative to the position shown in FIG. 8, such that a narrow channel 152 is created. One then pushes the trolley 120 up until the zip line 12 is seated in the channel 152.

With the trolley 120 in the position illustrated on the left side of FIG. 9, the zip line 12 will not insert more deeply than illustrated, because passage is obstructed by the housing plates 122, 124. Thus, after pushing the trolley 120 up so that the zip line 12 is in the channel 152, the upper rollers 128, 130 are pivoted around the axle 134 such that they are even closer together, thus opening the lower portion of the channel 152. At this point, the trolley 120 is swiveled around, out of the plane of FIG. 9, until the upper rollers 128, 130 ride atop the zip line 12, making the trolley 120 ready for operation, as shown in FIG. 9. The process can be reversed to remove the zip line 12.

There is a safety mechanism that prevents the trolley 120 from assuming the positions necessary to insert and remove the zip line 12, and that safety mechanism can be appreciated by comparing FIG. 8 and FIG. 9. The bracket 154 has a convexly-curved upper surface 155 that terminates just below the lower roller. When that bracket 154 hangs straight down, the upper surface 155 of the bracket 154 is too close to the lower roller 132 for the trolley 120 to pivot into the positions shown in FIG. 9—positions which are necessary to receive the zip line 12. The upper surface 155 of the bracket 154 interferes with the lower roller 132 and prevents the rotation.

However, as was also described above, a recess 156 is placed in the bracket 154 such that when the bracket 154 is rotated approximately 90°, into the position shown in FIG. 9, the recess 156 provides enough clearance for the bar 158 to slide to an upper extent of the slot 126. This allows the housing 122, 124 of the trolley 120 to rotate around axle 134 in the manner shown in FIG. 9.

The bracket 154 provides the primary connection points for the passenger's harness and tether 18, including an opening 159 at the lower end sized for a carabiner or another suitable piece of hardware, and a slot 162 that can be used to mount additional hardware. Because of this, the bracket 154 will typically be extended straight down during operation. If it does rotate slightly to one side or another, for example, because of the inclination of the zip line 12, that rotation would be unlikely to reach the angular position of the recess 156. Thus, even if the rollers 128, 130 come off of the zip line 12, the trolley 120 is unlikely to come off the zip line 12.

Speed Control Mechanism

FIG. 10 is a side elevational view of the trolley 120 similar to the views of FIG. 9, but in a slightly different operational position. As can be seen in FIGS. 8-10 and appreciated from the above description, the bar 158 forms the primary connection that holds the trolley 120 together. It rides within the slots 126 provided in each of the main housing plates 122. The slots 126 run in opposite directions (i.e., one has a positive slope and the other a negative slope). The bar 158 also passes through the bracket 154, and through a pair of plates 160. (The upper portion of one of the plates 160 is shown in FIG. 10.)

Atop and mounted to the axle 134 of the lower roller 132 is a toggle switch 164 that is biased, again by magnets 165, into a downward position. A downwardly-extending prong 166 is connected to the toggle switch 164. The prong 166 is sized to insert into and be seated within one of a number of speed selection positions 168, 170, 172, 174, 176 in the housing plate 122. As can be appreciated in this view, the speed selection positions are openings 168, 172, 174, 176, while one position 170 is a bend in the housing plate 122. (In the position 170, the prong 166 extends over the side of the housing plate 122 and is held in position by the bend at that position.) The positions 168, 170, 172, 174, 176 are arrayed along an arc adjacent to the toggle switch 164. The toggle switch 164 allows a user to select the degree of speed control desired by altering the amount the upper rollers 128, 130 pivot relative to the lower roller 132, which is mounted on the same axle 134 as the toggle switch 164. The prong 166 is sized such that it can insert into the smallest of the openings 168. The position shown in FIG. 10 is the maximum speed (i.e., no braking) position.

The details of the speed control mechanism are shown in FIG. 10, as well as in FIGS. 11-15, which are simplified, schematic views of selected components of the trolley 120, including the two upper rollers 128, 130, the lower roller 132, the bar 158, and the plate 160. The zip line 12 is shown in phantom between the upper and lower rollers 128, 130, 132.

The bar 158 that acts to connect the elements of the trolley 120 is carried by a pair of corresponding elongate slots 178 with rounded ends, within the pair of plates 160. As shown in FIGS. 11-15, one upper, inner face of each slot 178 acts as a rack 180. A pair of corresponding pinions 182 is provided on the same axle 134 as the lower roller 132, beneath the toggle switch 164. As the toggle switch 164 is actuated and the assembly 132, 134, 164, 182 is rotated clockwise, the rack and pinion 180, 182 engage, and the lower roller 132 is pivoted without any linear displacement. However, the rack and pinion 180, 182 moves the plates 160, which moves everything else, so that the lower roller 132 is brought into varying degrees of engagement with the zip line 12.

Thus, in contrast to the trolley 16 described above, in which the fourth roller 52 is moved up and down, in the trolley 120, the lower roller 132 does not move up and down; rather, everything else moves around it. This occurs because when the rack and pinion 180, 182 engage and move relative to one another, the bar 158, which is carried by the plates 160 of which the racks 180 are a part, is moved into various vertical positions along the slot 126. That is, the bar 158 is the central point or axis around which everything else rotates or pivots, and it is moved, thus causing the relative positions of the other components to change. For example, when the bar 158 is closest to the lower roller 132 and axle 134, the lower roller 132 would not be expected to make much or any contact with the zip line 12; however, when the bar 158 is furthest from the lower roller 132 and axle 134, the lower roller would be expected to make the most contact with the zip line 12. In other words, the toggle switch 164 controls the position of the bar 158, which limits the extent to which upper rollers 128, 130 pivot around the lower roller 132 and axle 134. When upper rollers 128, 130 are closer together, little to no engagement of the lower roller 132 should occur, whereas when the rollers 128, 130 are farther apart, a greater amount of lower roller 132 engagement is expected to occur on the zip line 12.

FIGS. 11-15 show a progression of positions, from the fastest speed setting (FIG. 11), in which the rollers 128, 130, 132 are not in contact with the zip line 12, to the slowest speed setting (FIG. 15), in which the position of the rollers 128, 130, 132 causes a localized deflection of the zip line 12 and increases the friction on the zip line 12. While five distinct speed settings are available in the trolley 120, more or fewer speed settings may be used in various embodiments. In some embodiments, there may be only two settings: no speed reduction and speed reduction.

FIG. 16 is a perspective view of the trolley 120 in isolation, illustrating an optional passenger handle, generally indicated at 184, engaged with the trolley 120. The handle 184 comprises a series of parts that enable it to be foldable, lightweight, and securely engaged with the trolley 120, including a long piece 186 that acts as a connecting point to the bracket 154 of the trolley 120. The long piece 186 comprises a slot-engaging member 196, complementary and corresponding to slot 162, which is disposed above a rectangular slot 198 configured to receive the carabiner loop 159 of the trolley 120. FIG. 16 illustrates that when the long piece 186 of the handle 184 is engaged to the bracket 154, a carabiner may be inserted into the loop 159, thus securing the handle 184 to the trolley 120.

Additionally, the long piece 186 is sandwiched between two smaller outer plates 188. These outer plates 188 cover the pivoting connection between the long piece 186 and two elongate grips or holds 190, which are intended to be held by the passenger P. The holds 190 are rotatable between two positions: the position illustrated in FIG. 16, which will be referred to as “open,” and a position with the holds 190 folded, which will be referred to as “closed.” When the holds 190 are in the closed position, the holds 190 generally make a vertical line parallel to the long piece 186. However, when the holds 190 are disposed in the open position, the holds 190 generally extend orthogonally from the long piece 186 of the handle 184. The handle 184 may be biased in an open or a closed position with a series of corresponding magnets 194 disposed in the holds 190 and the long and short pieces 186, 188.

FIG. 17 is a partial schematic elevational rear view of the handle 184, in isolation. The holds 190 are shaped to have an ergonomic design along an upper surface of the handle 184, for the hands of a rider P, when disposed in an open position. For example, the holds 190 of FIG. 17 are designed to have rounded cut-outs for at least three fingers of the rider's P hands. The holds 190, in some cases, may have gear teeth on corresponding outer surfaces near the pins 192, making the inwardly-facing surfaces of the holds 190 into spur gears, such that the two holds 190 abut and mesh. This makes their positions dependent and maintains them in corresponding, symmetrical positions. Whereas such gearing is expected to keep the handle 184 in an either open or closed position, in other embodiments, the holds 190 may have smooth outer edges, allowing the holds 190 to move independently. Additionally, generally any shape is expected to work for the holds 190, as long as they promote a secure connection to the trolley 120. In other words, in some embodiments, the handle 184 need not be foldable.

FIG. 18 is a front elevational view of the handle 184 in an open position. FIG. 18 illustrates there are number of circular holes 202 in the longer piece 186. These holes 202 are designed to reduce weight of the handle 184, without reducing structural integrity. While these holes 202 serve as an example, fewer or additional holes 202 may be placed on the handle 184, and the locations of the holes 202 may vary.

FIG. 19 is a rear elevational view of the handle 184 in a closed position. In this figure, the holds 190 are folded in-line with the longer piece 186. In other words, the holds 190 are generally parallel to each other. When the holds 190 are folded in a closed position, the ergonomic design of the upper surface of the holds 190 may correspond with the holes 202 of the long piece 186. The spacing of these holes 202 aligned on the longer piece 186 may vary, and additionally, the ergonomic features of holds 190 may vary in both shape and position. FIG. 19 additionally illustrates the spur gearing on the holds 190.

Both trolleys 16, 120 are typically constructed of metal parts, although certain parts, including the housings, may be made of composites or other materials in some embodiments. Steel and aluminum are both suitable materials, and some components may be anodized or otherwise surface treated to resist weather and wear.

Although this description refers to a “speed control mechanism,” it is possible that under certain conditions of inclination, wind speed, and passenger weight, certain speed settings may bring the trolley 16, 120 to a stop. Thus, a course operator will generally select the appropriate degree of speed reduction for a particular course, taking into account the relevant factors to give a passenger just the amount of energy necessary to reach the end of the zip line 12 at a reasonable speed.

That said, the mechanisms of trolleys 16, 120 according to embodiments of the invention may be advantageous as compared with traditional braking systems for several reasons. For one, trolleys 16, 120 according to embodiments of the invention apply a consistent, rolling speed reduction over the entire length of the zip line. Braking systems do not typically do this. Whether the brake in question is a gloved hand or a mechanical brake, brakes are typically applied suddenly and unevenly by the passenger, which means that using a brake might inadvertently remove too much energy, leaving the passenger stopped and stranded in the middle of the zip line.

Additionally, a top-loading feature allows more flexibility in how the passenger is attached to the trolley—specifically, the passenger can be attached either before or after the trolley is placed on the zip line.

While the speed control mechanism described above has advantages over traditional brakes in providing consistent speed control across the zip line 12, brakes 22, 24 may be used to bring the trolley 16, 120 and passenger P to a stop at the end of the zip line 12. A secondary brake 24 was described briefly above. FIG. 20 is a perspective view of the secondary brake 24, which statically engaged with the zip line 12. As was described above, with respect to FIG. 1, the secondary brake 24 essentially serves as an emergency brake, in the event that the primary brake 22 does not slow and stop the passenger P sufficiently before the zip line support 14. While the primary brake 22 is expected to gradually slow a rider P until they stop, the secondary brake 24 is intended to abruptly stop a rider P upon impact. The secondary brake 24 causes this abrupt stopping force because it is essentially clamped on the zip line 12. This clamping occurs between an upper portion 204 and lower portion 206 of the brake 24, as will be described in more detail below.

As can be appreciated from FIG. 20 and from FIG. 21, an exploded perspective view of the brake 24, the upper portion 204 of the brake 24 has a channel 212 that fits over the top of the zip line 12, while the lower portion 206 is arranged such that it makes an adjustable contact with a lower surface of the zip line 12. The lower portion 206 of the brake 24 comprises a tapered rod with an upper hole 208 and a lower hole 210; the lower hole 210 is centered and serves as a connection point for the brake line 28. The upper hole 208 is not centered (i.e., it is eccentric). The upper portion of the housing 204 terminates in a pair of depending support bars 216 with openings. To connect the upper and lower portions 204, 206, one places the lower portion 206 between the two support bars 216 and inserts a coupler-locking pin 214 through the hole 208 and the two support bars 216, thus connecting the upper portion 204 to the lower portion 206. The upper surface of the lower portion 206 has a rounded lobe 220 and acts as a cam with its eccentrically-placed hole 208.

The slots 216 are elongate and straight, whereby they are longer than their width. The width of the slots 216 correspond to a diameter of the pin 214, such that the pin 214 may be inserted into both slots 216 and the lower portion 206. The length of the slots 216 allows for a vertical adjustment to the pin 214, which affects the position of the lower portion 206 which is carried by the pin 214. Adjustments to the height of the lower portion 206 may be useful if, for example, different diameters of zip lines 12 are used, or the level of braking force requires an adjustment. The height of the lower portion 206 may be adjusted with a series of set screws 218, located in corresponding threaded holes (not shown) terminating in a lower extent of the slots 216. An upper extent of the screws 218 are expected to be the surface upon which the pin 214 is carried, once inserted into the slots 216, and through the lower portion 206. Thus, the setscrews 218 allow for a fine adjustment to the vertical position of the pin 214, and also the height of the lower portion 206 relative to the zip line 12. For example, turning the setscrews 218 in a clockwise direction is expected to raise the pin 214 and lower portion 206 (e.g., closer to the zip line 12), while turning the setscrews 218 in a counter clockwise direction is expected to lower the pin 214 and lower portion 206 (e.g., farther from the zip line 12).

FIG. 22 is a partially schematic side elevation view of the secondary brake 24 installed on a zip line 12, disengaged and able to slide freely along the zip line 12. In order to move the brake 24, the operator may push or throw the brake 24 to a desired position, or they may pull the attached brake line 28 until the brake 24 is in position. FIG. 22 illustrates that the lower portion 206 pivots around the pin 214 in a clockwise, or a counter-clockwise direction (i.e., 180° of pivoting motion) until it is essentially parallel to the zip line 12. When the lower portion 206 is pivoted in parallel with the zip line 12, it is expected to move freely on the zip line 12. The brake 24 may be moved, engaged, or disengaged using the brake line 28. Additionally, magnets 44 disposed along the brake line 28 are expected to prevent accidental tangling with the zip line 12, as was described above in more detail with respect to FIG. 1.

FIG. 23 is a partially schematic side elevational view of the secondary brake 24 installed on a zip line 12, engaged to abruptly stop a trolley 16 and a rider P. When the brake 24 is engaged to stop a trolley 12, the lower portion 206 extends generally orthogonally relative to the zip line 12, with its lobe 220 extending upward. When the lower portion 206 is in this position, the cam lobe 220 applies pressure to the zip line 12, increasing the normal force, and thus, the friction between the zip line 12 and brake 24 to a point where the brake 24 cannot be moved.

While the invention has been described with respect to certain embodiments, the embodiments are intended to be exemplary, rather than limiting. Modifications and changes may be made within the scope of the invention, which is defined by the appended claims.

Other embodiments of the invention will be apparent to those skilled in the art from consideration of the specification and practice of the invention disclosed herein. It is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the invention being indicated by the following claims. 

What is claimed is:
 1. A trolley, comprising: a housing; a first roller and a second roller connected to the housing and spaced from one another, the first and second rollers being adapted to rotate; a lower roller mounted movably within the housing and placed in opposition to the first and second rollers, the lower roller being movable in a direction that takes it closer to or farther away from the first and second rollers.
 2. The trolley of claim 1, further comprising a channel provided along a top surface of the trolley, the channel configured to allow the first and second rollers to be seated atop a zip line with the zip line within the trolley.
 3. The trolley of claim 1, further comprising a channel formable along a top surface of the trolley, the channel comprising an opening to allow the first and second rollers to be seated atop a zip line with the zip line passing through the trolley.
 4. The trolley of claim 1, the lower roller further comprising a rotatable pivoting plate and a linkage wherein said lower roller is configured to adjust the speed of the trolley.
 5. The trolley of claim 1, wherein the lower roller promotes braking of the trolley when the lower roller is moved in a direction that is closer to the first and second rollers.
 6. The trolley of claim 1, further comprising a clutch bearing coupled to the trolley and a third roller, wherein the clutch bearing is configured to prevent the trolley from rolling backwards.
 7. The trolley of claim 3, the channel further comprising a gate biased toward the closed position.
 8. The trolley of claim 1, further comprising a capture barb configured to engage a cavity of a brake disposed on the zip line.
 9. The trolley of claim 1, the zip line further comprising a brake disposed on the zip line to receive and capture the trolley.
 10. The trolley of claim 8, the capture barb further comprises magnets to bias the position of the capture barb.
 11. The trolley of claim 2, further comprising a magnetic rope connected to a brake and the zip line, wherein said magnetic rope is ferromagnetically attracted to the zip line.
 12. A trolley, comprising: a housing; a first roller and a second roller connected to the housing and spaced from one another, the first and second rollers being adapted to rotate; a lower roller mounted within the housing and placed in opposition to the first and second rollers, the first and second rollers being movable in a direction that takes the first and second rollers closer to or farther away from the lower roller.
 13. The trolley of claim 12, further comprising a channel formable along a top surface of the trolley, the channel configured to allow the first and second rollers to be seated atop a zip line with the zip line passing through the trolley.
 14. The trolley of claim 12, further comprising a switch configured to adjust the speed of the trolley by altering a position of the first and second rollers relative to the lower roller.
 15. The trolley of claim 12, further comprising a clutch bearing coupled to the trolley and a third roller, wherein the clutch bearing is configured to prevent the trolley from rolling backwards.
 16. The trolley of claim 12, further comprising a capture barb configured to engage a cavity of a brake disposed on the zip line.
 17. The system of claim 12, further comprising a tether coupled to the trolley.
 18. The system of claim 12, further comprising a brake configured to stop the trolley before it reaches a support.
 19. The trolley of claim 12, further comprising a handle coupled to the trolley.
 20. A method of controlling speed of a trolley, comprising: advancing a trolley adapted to ride on a zip line along a specified direction of travel; engaging, with a zip line, a first roller, a second roller, and a third roller connected to a housing, said first roller, said second roller, and said third roller spaced from one another; and adjusting the speed of the trolley by moving a position of said first, second, and third rollers relative to the zip line. 